The invention relates to medical devices or tools for performing surgical procedures, including heart valve repairs. In particular, the invention relates to devices with bendable tips for positioning medical instruments during invasive procedures, preferably minimally invasive procedures.
Endoscopes, orthoscopes, probes, catheters and the like can be inserted into a patient for the performance of various medical procedures. To perform the procedure, a particular instrument is positioned at the appropriate location within the patient. The procedure can involve one or more processes, such as imaging, tissue ablation, tissue repair, tissue cutting and combinations thereof. These procedures can involve vascular, intestinal, urological, vaginal, oral or percutaneous delivery of the instrument to the specific location for performing the procedure. Procedures for the repair of a damaged or diseased heart, especially to correct heart valve insufficiency, are of particular interest.
Heart valve insufficiency can be a debilitating and possibly life threatening condition. For example, heart valve regurgitation, i.e., backward leakage of blood at a heart valve, results in reduced pumping efficiency. With respect to mitral valve regurgitation, compensatory mechanisms such as hypertrophy and dilation of the ventricle suggest early treatment to prevent progressive deterioration of ventricular function. Diagnosis of mitral regurgitation can be performed using visualization with transesophageal echocardiography or by echocardiography. In particular, defective leaflet coaptation and the site and direction of the regurgitant flow can be examined to evaluate likely modes of failure.
Mitral valve prolapse, i.e., myxomatous degeneration of mitral valve leaflets, is the most common cause of mitral regurgitation in North America. Rheumatic heart disease was the most common cause of mitral regurgitation in the U.S.A. thirty years ago and is still the most common cause of mitral regurgitation in developing countries. Chronic rheumatic heart disease results in retraction, deformity and rigidity of one or both mitral valve cusps as well as structural abnormalities in the commissures, chordae tendineae and papillary muscles. Ischemic mitral regurgitation (IMR), i.e., anemia of the valve tissue due to reduced arterial blood flow feeding the valve tissue, is the second most common cause of mitral valve regurgitation. Studies suggest that annular irregularities and posterior papillary muscle fibrosis with scarring of the underlying ventricular wall may be associated with IMR.
Many cases of mitral regurgitation can be repaired by modifications of the original valve in a procedure generally referred to as valvuloplasty. These repair procedures typically involve a full sternotomy and quadrangular resection of the anterior leaflet, while on cardiopulmonary bypass. Repairs can also involve reattachment of chordae tendineae, which tether the valve leaflets, or removal of leaflet tissue to correct misshapen or enlarged valve leaflets. In some cases, the annulus of the valve is secured using an annuloplasty ring. Valves that are heavily calcified or significantly compromised by disease may need to be replaced.
As an alternative to these repair techniques, an edge-to-edge suturing of the anterior and posterior mitral valve leaflets can be performed. Commonly referred to as a xe2x80x9cbow-tiexe2x80x9d repair, edge-to-edge suturing ensures leaflet, coaptation without performing a quadrangular resection of the anterior leaflet. The bow-tie repair generally involves the use of a centrally located suture, although a suture can be placed close to a commissure, or multiple sutures can be used to complete the repair. A centrally placed suture creates a double orifice valve, which resembles a bow-tie.
The edge-to-edge repair procedure has been applied using invasive procedures by placing the patient on extracorporeal circulation. An incision is made to provide access into the left atrium of the heart. Following suturing, the atrium is closed. Such repairs can result in a significant decrease in mitral regurgitation along with a corresponding increase in the ejection fraction. Corresponding repairs can be performed on tricuspid valves.
In a first aspect, the invention pertains to a device for medical procedures comprising a shaft, a bendable tip and a fastener applicator. The shaft has a distal end and a proximal end. The bendable tip extends from the distal end of the shaft. The fastener applicator extends from the bendable tip. In some embodiments, the bendable tip includes a plurality of articulating segments.
In a further aspect, the invention pertains to a device for medical procedures comprising a shaft, a malleable section, a bendable tip and a control mechanism. The shaft has a distal end and a proximal end. The malleable section extends from the distal end of the shaft. The bendable tip extends from the malleable section. The control mechanism is connected to the bendable tip wherein the control mechanism comprises a knob. The adjustment of the knob controls the bend of the bendable tip.
In another aspect, the invention pertains to a device for medical procedures comprising a shaft, a bendable tip, a handle, a knob and a cord. The shaft has a distal end and a proximal end. The tip extends from the distal end of the shaft. The handle has a grip generally coaxial with the shaft, and the handle is attached to the proximal end of the shaft. The knob rotates around the axis of the grip. The cord connects the tip with the knob such that rotation of the knob in one direction retracts the cord to bend the tip.
In addition, the invention pertains to a method of repairing a heart valve including inserting a device through the catheter and performing a repair of the heart valve with the medical instrument. The device includes a shaft, a bendable tip extending from the distal end of the shaft and a medical instrument extending from the bendable tip. In some embodiments, the method includes placing a catheter extending within the heart, and the insertion of the device includes introducing the device through the catheter.